The day of the year is in the array returned by
localtime() (see
localtime):

$day_of_year = (localtime(time()))[7];

or more legibly (in 5.004 or higher):

use Time::localtime;
$day_of_year = localtime(time())->yday;

You can find the week of the year by dividing this by 7:

$week_of_year = int($day_of_year / 7);

Of course, this believes that weeks start at zero. The Date::Calc module from
CPAN has a lot of date calculation functions, including day of the year, week of the year, and so on. Note that not all business consider ``week 1'' to be the same; for example, American business often consider the first week with a Monday in it to be Work Week #1, despite
ISO 8601, which consider
WW1 to be the frist week with a Thursday in it.